textproduct: Rapid City

KEY MESSAGES

- Dry conditions this weekend with no thunderstorms expected.

- Very hot this weekend with highs in the 90s and lower 100s on the Plains, before a brief relative cool-down early next week.

- Elevated to near-critical fire weather conditions this weekend into Monday.

UPDATE

Issued at 1051 PM MDT Fri Jul 31 2026

No major changes were needed with this evening's forecast update. Great consensus among the CAMs in no isolated thunderstorm risk this weekend. Sunday still looks like the hottest day and best candidate for at least a few of our South Dakota plains zones to need Heat Advisories, but still somewhat marginal and will continue to hold off on any issuances this early. Speaking of temperatures...have you seen Tuesday's forecast?! It's only for one day, but highs holding in the upper 60s over the Black Hills to the upper 70s across northeast Wyoming and our South Dakota plains!

DISCUSSION

(This Afternoon Through Thursday) Issued at 1121 AM MDT Fri Jul 31 2026

Western CONUS upper ridge will shift east into the Northern Plains and support hot and dry weather as a stronger upper trough moves into the Pac NW. Weak shortwave advecting into the FA today and will merge with the deeper trough over the upper Midwest. Lingering moisture and weak CIN will allow a few showers and isolated TS to develop across the western third this afternoon, specifically northeast WY, the southern BH, and maybe far NW SD. Lack of appreciable CAPE and insufficient deep layer shear will support weak pulse convection. Hence, severe weather is not expected other than gusty winds. Convection will quickly wane this evening. Thermal ridge will slowly shift east ahead of the advancing NW Pac upper trough, supporting hot conds Sat and Sun. The warmest day will be Sunday when highs will reach the lower 100s at many locations on the Plains. A heat adv may be needed on portions of the SD Plains Sunday as heat index readings will reach 100-105 in some areas. Lee-side trough will settle into the FA Sunday. However, cooler air won't advect into the FA until Monday when highs will be in the 80s and low 90s, coolest NW. Stronger cold front will arrive Monday night, which will really knock temps down for Tue. This system may also support some convection Monday night as the entrance region of the upper jet will push through the region coupled with deep layer ascent and sufficient moisture. Highs will mainly be in the 70s Tue, the first below normal day in long while. Western ridge will flatten as a deep upper low slowly pushes east across interior Canada. This will support a slow warm up as SE return flow ensues. Increasing LL moisture will support isolated TS chances by Wed as weak impulses advect through the region in NW flow.

AVIATION

(For the 12Z TAFS Through 12Z Sunday Morning) Issued At 534 AM MDT Sat Aug 1 2026

VFR conditions are expected through the TAF period.

UNR WATCHES/WARNINGS/ADVISORIES

SD...Heat Advisory from 10 AM to 8 PM MDT Sunday for SDZ013-014-026- 027-030>032-041>044-072>077. WY...None.